Syndrome: increase in glucocorticoids (primarily cortisol).
–Disease: this happens when the pituitary releases ACTH. ACTH will also cause other stuff to be elevated, such as androgens and MSH (POMC splits up into ACTH and MSH or melanocyte-stimulating hormone)… get other symptoms like hirsutism and hyperpigmentation. Will respond to high dose dexamethasone suppression test.
–Ectopic ACTH ( small cell carcinoma of the lung – bronchial carcinoma & thymoma). Will not respond to dexamethasone.
–Adrenal tumor: get low ACTH but high Cortisol.
Hypothalamus—PVN (paraventricular nucleus) à CRH à Pituitary à ACTHà Adrenal glands à Cortisol